This invention relates to a grindingg device for preparing the edge of a cutting tool used in machining operations.
More specifically, this grinding device is particularly suitable for providing a semicircular, longitudinal groove on the cutting face of a cutting tool which groove comprises a chipbreaker.
It has been discovered that the placement of a semicircular or eliptical groove on the cutting face of a cutting tool displaced a short distance from the cutting edge will cause the ribbon-like continuous chip to break into short chip particles. This is desirable not only for convenience in handling cleanup and disposal of waste metal in chip form, but to prevent the chip in ribbon form from fouling the cutting operation, or particular concern in automatic or semiautomatic cutting operations.
However, the precision with which the chipbreaker groove must be dimensioned and located on the cutting face of the cutting tool enables only the most highly skilled of the machinists to properly prepare a cutting edge. Because each material being machined may require a somewhat different optimum cutting edge configuration, which may further vary due to cutting speed, depth of cut, radius of piece, etc., the edge preparation becomes an art based on a machinist's ability and experience. Because these cutting edges are hand ground (except where factory prepared), it is virtually impossible to convey information about cutting edge specifications except through demonstration and visual inspection.
While proper preparation of a cutting tool edge having a chipbreaker is a primary use of the invented machining device because of the extreme difficulty of this operation, the machining device can be used for preparation of other complex edge configurations. For example, certain cutting operations can best be performed with a cutting tool having a "K" land at the cutting edge which is a chamfer or bevel also known as a land angle incorporated into the tool edge.
Because of the complexity of these exotic edges, cutting tools are often provided with factory prepared inserts which are discardable after the life of the factory prepared edge. The inserts are generally not repairable by grinding to rehabilitate a worn or chipped edge. The use of inserts, however, restricts the user to certain fixed edge configurations and is often an added expense only because of the inability to properly prepare the cutting edge of a conventional carbide or tungsten tool. The precision of this grinding machine permits factory prepared inset to be repaired or altered for optimum cutting.